1. Field of the Invention
The present invention relates to a composition comprising at least one sapogenin in a physiologically acceptable medium.
2. Description of the Background
Sapogenins are compounds resulting from the acid hydrolysis of saponosides, which are heterosides of very high molecular weight present in the plant kingdom. Examples of sapogenins include: diosgenin, hecogenin, smilagenin, sarsapogenin, tigogenin, yamogenin and yuccagenin.
These compounds have in common a steroidal structure comprising a variable number of hydroxyl and/or oxo substituents and/or a variable number of double bonds. They are known as natural chemical precursors of steroidal hormones and are described, in this respect. as constituents of choice for various cosmetic or pharmaceutical preparations. U.S. Pat. No. 5,827,884 also discloses the use of these compounds for their anti-inflammatory properties and as cell growth stimulants.
A preferred sapogenin is diosgenin, or spirost-5-en-3-beta-ol, which can be extracted from fenugreek or from various Dioscorea plants, for example from the root of wild yam.
However, it has been found that diosgenin is difficult to dissolve, and thus to formulate, in solvents that are physiologically acceptable for topical application to the skin, on account of its high melting point (close to 204-207.degree. C.) and its tendency to recrystallize in these solvents.